


Burnin'

by skymori



Category: Voltron: Legendary Defender
Genre: Affectionate top Shiro, Alpha Shiro (Voltron), Alpha/Beta/Omega Dynamics, Alternate Universe - College/University, Alternate Universe - Modern Setting, First Time, Knotting, M/M, Mating Cycles/In Heat, Omega Keith (Voltron), Pet Names, Sheithlentines 2021, sick fic except not really
Language: English
Status: Completed
Published: 2021-03-09
Updated: 2021-03-09
Packaged: 2021-03-15 16:07:43
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 7,537
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29935944
Author URL: https://archiveofourown.org/users/skymori/pseuds/skymori
Summary: “Baby,” Shiro asks carefully, not wanting to risk offending him. “Do you not know what a heat is?”Wherein Keith comes down with a "cold" right before exams start, and Shiro, loving Alpha Boyfriend Extraordinaire, knows exactly how to help.
Relationships: Keith/Shiro (Voltron)
Comments: 14
Kudos: 154
Collections: Sheithlentines 2021





	Burnin'

**Author's Note:**

> This is my ultra-late Sheithlintines for Starry! I'm so fucking sorry it took so long to get out, but I hope you like it nonetheless!!
> 
> Featuring ABO and First time sex.

“Are you sure you don’t want me to come over today?” Shiro asks from the other end of the receiver. The concern, the kindness, and all of the mans inexplicable endearment for his boyfriend not lost despite the fuzzy reception of Keith’s phone. “There might not be another chance to re-take this.

Keith shakes his head no, and realizes only mid-shake that Shiro can’t see it. He’s holed up in bed, dizzy, red-faced, with a pounding headache. And for the last five hours, Keith hasn’t been able to decide whether he wants every blanket in his house swaddling him, or burning in the nearest bonfire. He switches between sweats and shivers every ten minutes. If there were a color changing competition, Keith’s pretty sure he could go up against a chameleon right now and win.

“No,” He sighs, rereading the temperature on his thermometer for the umpteenth time. 106 Degrees. “I don’t want to get you sick too.”

It’s 4:45pm at Keith’s little apartment, and what was supposed to be a study session for their college exams (and potentially movie night) with his significant other is now quickly looking to be a cancellation plan. Both for his date, and for his future.

"You don’t need to worry about that. I got my flu shot months ago.” Shiro says, and Keith thinks back to about six months ago when said shots had come out, and mentally slaps himself for failing to get his own at the time.

“I’m guessing you didn’t.”

Keith scowls into the air. “It slipped my mind.”  
  


When Shiro resounds with an amused chuckle, Keith huffs. “Glad you find my pain so funny.”

“Oh, no” Shiro says, but the laugh doesn’t leave his voice at all. “I just think it’s cute. Of all things to bring you down, of course, it’s a cold.”

“Bring down This,” Keith says vengefully, and then blows air hard into the receiver. Shiro gasps and squeaks on the other end, followed by a sudden _thump_ sound of which Keith’s pretty sure is Shiro dropping his phone.

“Ha-Ha.” Shiro replies, after some fumbling. “Are you happy?” It’s like Shiro can see his smirk.

“Yes.” Keith says, and then thinks better of it. “..No.” He was going to fail his last semester of college, and he wasn’t even going to get the comfort of his boyfriend there before it crushed him.

“That’s what I thought, which is why I’m coming over anyways.”

Keith would be lying if he said his heart didn’t pang a little at Shiro’s decided tone. But that still didn’t mean he could roll over and let it happen. “I can’t concentrate on studying right now anyways. Coming over won’t accomplish anything besides getting you sick too.”

“I already told you, I’m not going to get sick. And even if you can’t study, you and I both know we had more planned tonight than just that.”

“I—Well. That’s true.” Shiro’s spare jacket hangs on the back of a chair from across Keith’s bed, and well. They weren’t _Not_ turning these nights into dates and sleepovers.

“Mhmmmm,” Shiro hums. “And what kind of boyfriend would I be if I just let my sweet little baby be sick and alone right now?” He asks. Rhetorical as it is, it sets fire to Keith’s already hot face, destroying any sense of cognition he’d had left. “I—you—“ 

It’s true. Were it Shiro, there would be little to nothing Shiro could’ve said to deter Keith from coming over to take of him, and he knows it.

There’s a chuckle from the other end, and Keith almost drops his phone. Shiro’s endeared little laughs is electricity, sending little shockwaves to his ears. “I’ll be over soon sweetheart.”

“I’ll _Over_ your _Soon!!_ ” Keith barks back, flustered and chronically incapable of handling affection—but his efforts only earn himself more endeared laughs. Pidge overheard them like this once, and said Keith was failing the Turing Test. The resulting imagery of Keith shorting his circuits has since embedded itself within the group, and Shiro laughs even louder, no doubt reminded of it too.

“I’m going to pick up some medicine and tea for you on the way there. Is there anything you want me to get?”

“I don’t know. A clue? A chill pill? A sense of self-preservation?”

“Just for that, I’m picking up your favorite food.”

Keith groans loudly in complaint, and then sighs. His will to resist wavering by the second.

“I love you. I’ll be there soon.” Shiro says, making a kissy noise into the receiver. Keith used to cringe at over the top lovey dovey affection like this in other couples. Now he melts and smiles with every little one he hears.

“Love you too.” He says, his voicemuch too sincere to be the begrudging eye-roll laden thing he would like it to be.

Shiro hangs up, and Keith’s left smiling at his phone like a dope for about ten minutes before he sighs and gets up to try and make himself somewhat presentable.

Around 40 minutes later, Shiro arrives at Keiths door with his distinctive soft little knock, and Keith—Freshly showered and hastily pulling on what little clothing he hasn’t already soaked through—Ambles haphazardly to the door with a little call of “Coming!”

“Hey,” He greets. His hair is still dripping slightly from his shower over onto his soft worn tee, which drapes over his too-small frame and slightly over the grey sweats at his hips.

“Hey yourself.” Shiro greets back, only for his easy, warm smile to promptly drop into a look of muted surprise. Keith opens the door wider for him to enter, but Shiro stands frozen and staring into the air.

“What?” Keith asks, and sniffs at the air. “Does it smell?” Sure, he’s a little behind chores, but his place can’t stink _that_ bad.

“Oh, ah-- no.” Shiro waves his hands, quickly recovering his composure. “It’s nothing. Here.” He says, offering the pizza boxes and small plastic bag in with one hand. “I’ve got your favorite. May I come in?”

Keiths puzzled face quickly softens into a melty little smile, and he pushes the door further open for Shiro. “Of course.”

“Thank you,” Shiro says, even though he doesn’t have to. Doesn’t even have to ask, really. Keith’s home is as much his as it is Shiro’s as far as he’s concerned. But as Shiro walks in and sets down his keys, pizza, and little plastic bag of whatever cold-remedies he’s picked up, Keith can’t help but note that the tension from earlier hasn’t quite left his frame.

Concerned, Keith closes the door, but doesn’t yet lock it. “You really didn’t have to come, you know.” He says. “I would’ve been fine on my own.” The older man seemed perfectly fine to come before—More than fine. Stubborn even. Unrelenting. But Keith can’t help but offer him an extra out just in case it’s changed.

But of course, Shiro doesn’t take to the bait. “What?” He calls over his shoulder. There’s a crinkling from the bag, and a ruffling from where Shiro is taking out a couple tiny boxes and opening them. “Nonsense. We had a date tonight-“

“A study date.”

“And I’m not letting you be miserable all by yourself. Now come here.” Shiro says, smiling. Keith can’t tell whether Shiro has just successfully masked his earlier irritation, or whether hes genuinely overcome it. He supposes maybe it wasn’t all too cumbersome in the first place, and finally locks the door behind him before padding over to the table.

“I wasn’t sure which one to get you, so I got a couple.” Beneath the man are several small boxes of medicines, teas, and one bag of cough drops. Shiro presents them all to Keith, before pressing a small kiss to his too-hot forehead. “Pick one out for me, while I put on some water.” He says, and shucking off his shoes at the door and making his way to the stove.

Rubbing at the spot on his forehead where Shiro kissed him, Keith gently goes over some of the tea boxes. They’re all medicine-marketed brands for throat-soreness. One is a saturated grey green, another is a bright pink, and a third is a bright orange-red, adorned with images of cinnamon sticks and lemons. Tea is one of those things that always seemed too frivolous for Keith to concern himself with. Like celebrity gossip, fashion trends, or Lance. So he shrugs, taking the orangy-red box and joining Shiro at the stove, where the older man has fished out a pot to replace his missing kettle, and is currently warming up some water to boil.

Keith presses the little box silently into Shiro’s offered hand like it’s not his gift, and Shiro hums at the selection. “Cinnamon –Apple, huh?”

Keith blanches a little at the affectionate way Shiro speaks. Why does he have to be so happy about it? “Yeah?” He asks. “Is there something wrong with it?”

“No.” Shiro says, opening the little package up and setting it aside for later. “It’s just cute.”

As if his head wasn’t already reeling from the cold. “Agefbupht-“ Keith blurts out-- and no, he’s pretty sure he doesn’t know that language either-- “Cute?” The world spins. Keith’s hand juts out for the counter top to steady himself.

“Mhmm. Very.” Shiro says like it’s nothing, and then shoots a smile at him—A little side smirk from his peripheral towards him. “I thought you might like it. It suits you.”

It should be illegal to say things like that so casually. Keith really has no response for that, save for staring, before hiding his face. It really should be illegal. If nothing else, while he’s already burning up from head to toe. His balance is normally great, but the room spins with Shiro in it. His head pounds from all sides, muting his thoughts into slush and slurry. He can’t tell where one ends and the other begins, while the pressure of keeping himself presentable mounts higher and higher under Shiro’s affectionate gaze. And as if on cue, Shiro’s free arm reaches out and behind Keith’s back, before pressing him to lean against his side. Automatically reaching out to steady him.

Keith muffles out a little “Thank you,” and he feels more than hears the way Shiro hides his chuckle, pressed into his side as he is, hiding his face. “Not a problem.”

Sweet and comfortable, it only takes a minute for Keith to relax into the loose, warm hold. The scent of Shiro has always been a pleasant, comforting one. But something about it tonight is especially encompassing. Keith attributes it to how absolutely shot his other faculties are right now and thinks nothing of it as he sighs and breathes in more of Shiro’s woodsy oxygen rich scent. Exhaling audibly into his chest in a way that makes shiro chuckle. But that’s fine. Shiro can chuckle all he wants. With one hand pressing him into the man he loves while tea slowly begins to boil behind him, homey and private in his little kitchenette, Keith is all but floating on cloud nine.

And then he feels a large mass of slick positively drop right out of him where he stands. Right into the seat of his pajama’s.

“Keith?” Shiro asks from above, having evidently noticed Keith’s sudden rigidity in his arms. “Is everything okay?”

“Yaeh, Yeah.” Keith breathes more than he speaks, and gently breaks from Shiro’s hold. “I just need to sit down for a bit.” He can feel himself positively dripping again, and slowly shrinks from Shiro’s touch and over to his little kitchen table to sit in one of the wooden chairs he’d refurnished from many a desert roadside.

Keith sighs and slowly lets himself lean over the table in a crumpled heap, pillowing himself in his arms and willing the world to stop moving. This practice might’ve had some success, if Shiro didn’t tail him. Placing a little coffee mug of tea down, Shiro takes a seat in one of Keith’s tiny mismatched chairs. Something that Keith would’ve smiled or laughed at for how big Shiro is in them, if not for the pounding of his head.

“Headache?”

“Mhmmm.” Keith responds lazily, eyes closed.

Shiro lets his eyes glance over the little cast aside boxes of medicines and soon-to-be cold pizza, but doesn’t reach to grab anything just yet. Instead, he puts a hand to Keith’s forehead and feels the heat of his fever-- Noting how flushed he looks all over, from head to toe.

“Keith,” Shiro starts, withdrawing his hand and reaching for some of the ibuprofen across the table. “Are you sure this is a flu?”

Keith cracks open one eye to look at him. Shiro rips off one of the little paper labels and unscrews the lid off the container. “This looks more like a heat to me.”

“A heat?” Keith echoes, questioning and confused. Like Shiro just recommended him foreign food.

“Yes.” Stretching out a hand, Shiro brings Keith’s still warm tea closer to him and holds out two little circular tablets for him, which Keith takes without complaint. Holding his hand out for the pills before tossing them into his mouth , chasing it with some tea.

Keith sniffs at it, tongue working over the remaining flavor from his mug. “You were right.” He pouts. “I do like it.

With an approving smile, Shiro pushes on. “Do you know when your last cycle was?”

Finishing off another sip, Keith furrows his brows. “Cycle?”

That seems to stop Shiro for a bit. “Yeah. You know. Your… cycle of heats.” Shiro makes a circular motion with his hand somewhat awkwardly, unsure of how to more clearly demonstrate this.

There’s a slow, pregnant pause then. Keith waiting for Shiro to expand on the concept—And Shiro waiting for Keith to expand on his answers.

It’s odd, to say the least. Keith is an omega, and Shiro his loving Alpha. They’ve been dating as an official couple for some months now, (as opposed to before, where they’d been “dating” as friends for years.) So naturally, the topic of secondary sex-characteristics never came up. Before he’d just assumed they’d each taken care of themselves as most people do. But now, Shiro finds himself reminded of how Keith sticks out apart from other omega’s, in his independence and toughness. How he’s never seen him show signs of wilting or waning, even in front of Shiro. But none of that necessarily meant anything, of course.

Surely, Keith knew about heats.

But the clock ticks on, and Keith, in lieu of an answer, simply closes his eyes again, content in the silence. Taking another sip of his tea.

“Baby,” Shiro asks carefully, not wanting to risk offending him. “Do you not know what a heat is?”

Keith opens his eyes again and gives Shiro a lazy glance and a shrug. “Not really.” He answers, keeping his mug close to his lips. “I didn’t know what I was for most of my life. And our school system never went into it.” Keith takes another sip and shudders at the feeling of another gob of slick falling through him, eyes squinting shut for a moment, and then opening again with a sigh.

“Why?” he asks. “Aren’t they just for like. Weddings and stuff?”

Keith looks up and finds Shiro’s expression paling with concern. “Not at all.” Shiro’s soothing voice betrays the depth of worry he feels for his partner, even with an open dialogue going. “They’re incredibly important.”

When Keith doesn’t reply, Shiro continues. “Yes, they do have a place in ceremony. People often wait for their fiance to approach their next heat right before the wedding, so they can consummate their marriage but.. Well. Heats happen throughout an Omega’s entire life.”

“Oh.” Keith says, now seemingly more alert. He has the grace to look somewhat bashful. “Huh.”

“Do heats come with headaches?”

“Sometimes.” Shiro answers. “It’s different for everyone, but when you compare it with something like a flu, there’s a lot of overlap. During heats, it’s also common for omega’s to get fevers, high temperatures, dizzy spells. But not so much congestion, vomiting, stuffy nose, coughing or sore throats. You haven’t had any of that, have you?”

Keith gulps, and works down another long drink of tea. “No.” He answers, his voice coming out a bit meeker than he’d like it to be.

“So. What makes you think I’m having one right now?” He asks. It could, after all, just be a cold lacking some symptoms.

At this, Shiro’s expression turns a bit bashful. “I hope this isn’t too much to say but, I’ve been smelling it on you since I got here.” Shiro admits with a tinge of blush to his cheeks. Keith however, is left wide eyed and staring on in realization.

“You can smell it?”

Shiro nods. “Alphas can. I can smell youuuurr... your… um.” Shiro’s hands gesture nonsense into the air. Not quite sure how to softly describe what he’s trying to say either, and his hand motions really don’t convey much more either. “You, your…” Shiro clears his throat. “The… excretions. From your.. “

Keiths eyes go even wider, cutting him off with another shocked little, “OH.” While his face burns impossibly hotter. In a microcycle he relieves Shiro of his need to articulate the awkward concept, only to win and ever-embarrassed Keith as a result.

His hands fly to cover his face, even as Keith tries to scootch him and his chair away from Shiro in small increments. “Oh, so that’s what was putting you off earlier. I’m so sorry Shiro. I knew I shouldn’t have let you come over-“ Keith starts, but Shiro is already scootching himself and his own tiny chair after Keith, even as Keith inches his own away—Which results in a small chair race around the table.

A cacophony of squeaks and scrapes ensue, and Shiro can’t help but laugh a little. “Hey! Hey it’s okay, trust me it’s not a bad smell. I was just surprised, that’s all.”

“Still, Shiro. It’s so gross. I don’t want you to have to smell me soaking my underwear.”

“Keith, baby.” Shiro grabs Keith’s chair, his voice so full of endearment and warmth, laughing again when Keith continues to try and scootch his chair away to no avail. “Keith, sweetheart. It’s a nice smell.”

That makes Keith stop and stare. A small “Oh.” Of befuddled realization on his lips.

One second later, Shiro realizes what he’s just said, and has the decency to look a little bit ashamed for it. He turns his head away for only a moment, unsure of what to make of Keith’s bashful little reaction. Then turns his head towards his boyfriend once more, patient and soft. “You tell me how you love my scent all the time.”

It’s not phrased like a question, but Keith nods affirmation anyway. “Yeah.”

“Do you remember that time when you told me how good I smelled after my last rut? -Oompf.” Shiro muffles a laugh under Keith’s hand, which is now pressed flat against his mouth. “Okay I think I understand now.” Keith says a little bit too fast, and Shiro laughs some more before gently peeling his lovers hand off.

With a sudden pull, Shiro jerks one of the chair legs closer, carrying it and Keith right into his chest. Before Keith can scamper away, Shiro wraps his arms around him tight, locking him into a hug. “No more running away, okay?” Shiro asks, adoringly.

“You’re just fine. Having a heat is a perfectly natural thing for an Omega. And besides,” Shiro pauses, moving to bring his face closer to Keith’s and inhaling deeply from the crown of his head. It makes Keiths eyes widen, a flutter running up and down his back. Shiro exhales with a pleased sigh that makes Keith’s stomach jump, and leans in close to whisper, “You smell very, _very_ good, baby. “

With Shiro’s big hands around him, body pressed so close to his own-- Voice husked low and close to his ear, hot breath on his neck and Alpha scent inescapable— All thoughts of resisting (all thoughts in general, really) quickly come to a halt, as another large gush of slick plunges out of him and settles at the bottom of his already-slick soaked pants.

Shiro smells so good. Warmth and safety practically emanates off of his skin like heat waves blurring vision on a summer day—Clouding his senses, his priorities, his chaffed pride.

Keith sinks into Shiros shoulder, pressing his reddened face into whatever crevice he can find, as if it’ll stop Shiro from raising the hairs on his neck with his every inhale of his scalp and makes a muffled whine of protest into his shirt. 

“It’s bad enough I was already sick—In heat—Whatever. You had to make me horny too?”

Shiro, bless him, bursts into laughter. His whole frame shakes with it, and Keith hides a smile in his shoulder. It’s a welcome reprieve from the sudden onslaught of teasing, giving Keith a moment to collect himself.

“I’m sorry I turned you on baby.” Shiro says with such a mix of endearment and sincerity, it get’s Keith to huff a little laugh of his own.

Shiro isn’t all that sorry, and Keith isn’t all that bothered. They’re fine. He’s mostly just complaining for the sake of complaining, unsure how to further deal with the unholy amount of slick that’s collecting at the bottom of his pants—and soon to be Shiro’s lap.—And rightfully embarrassed about it. Shiro seems to understand regardless of what word’s Keith uses though, and doesn’t pry or poke more. Instead, a big hand begins to smooth up and down over his back in slow slides that have Keith lowering his eyelids to each and every stroke.

Relaxing into the touches, Keith collects himself. Breathing in and out, letting the heat on his cheeks slowly ebb. His thoughts beginning to return to him.

“You know..” Shiro speaks up, breaking the small silence that had formed between them. “If you wanted, I think I might be able to solve some of these problems of yours.”

This time, Keith doesn’t need any explanation to understand what Shiro’s getting at. A short sigh escapes his smaller form, and he brings his head up to rest his cheek on Shiro’s shoulder. It wasn’t as if his hindbrain hadn’t made this connection already, but he wasn’t expecting Shiro to bring up the topic himself either.

“It’s alright if you’d rather not. We don’t have to rush into anything before you’re ready, or before we’ve had a chance to talk about it. We don’t have to do anything at all. But all the same, I don’t think I’d be a very good Alpha if I didn’t make the offer, either.” Shiro chides.

There’s a small, muffled little laugh from his shoulder then. “You come into my house, tell me I’m having a heat, and then leave.” Keith jokes, giggling at the absurdity of the thought.

Shiro’s voice practicality bursts with mirth. A deep belly laugh rumbling lowly inside him, before breaking through his lips in a loud thunderous ranchor that makes Keith shake where he’s held. “Ahaha! Oh, Keith, you’re too funny.” Shiro says, filled with endearment and giving his back a few pats.

“But in all seriousness, it could help you return to schoolwork on time. Most omega’s tend to recover from their heats quickly, if they have an Alpha to help sate them.”

“Mmm...” Keith pouts, and snuggles into his shoulder a little more. “It’s not that I don’t want to – the understatement of the century. Becoming an official mated pair with Shiro had only been his dream since he was a teenager. “– But um.”

“Too soon? Shiro cuts in. “I understand. We don’t have to if you’d rather—

“No, no that’s not it! I do. I do want to. I just- I just um. Uh…“ Keith seems to struggle for the words, as his eyes struggle to maintain contact with Shiros, before the effort collapses altogether in favor of hiding his face. And then, almost as quickly as it was hidden, does Keith uncover it to speak again. Hands still cupping his cheeks, framing his cheeks. Their rosiness renewed all over again with the topic of choice.

“I haven’t um. I haven’t done it – Done that, with anyone before.”

As if expecting disgust, or dismissal, Keith looks to Shiro shyly—Only to be greeted with an astounded, silent stare. The moment passes, and still Shiro does not speak.

“Shiro?” He prompts, hoping it will shock Shiro out of his staring. But still, nothing.

Fuck. Is it really that bad? Did he put Shiro off so much that he can’t even comment? Keith bites his lips, anxiety creeping into his heart as he shifts nervously in his seat. “Is.. is that okay Shiro?” He tries once more. “I don’t really have any experience with this, but I still want our first time together to be good for you so.. Is it still okay if I – mphf—“ Whatever Keith had left to say is quickly swallowed down by Shiro. Grabbing him and kissing the life out of him with a suddenness that takes Keith’s breath away--literally and figuratively.

Shiro’s mouth moves over his own, sucking and kissing and melting Keith down on the spot.

They break away, red-faced and gasping for air. Shiro looks about as flushed and excited as Keith feels when he pants out, “Baby boy—“ And take’s Keith into his arms for another soft, firm hug. “It’s more than okay. “

And there’s no hiding any of his smiles after that. One second Shiro’s arms are locked around him, tender and protective, and the next, he’s shifting them down and up again. Locking one arm around his knees and scooping him up into a bridal carry that makes Keith suddenly very aware of what they’re about to do. So he holds tight to Shiro’s chest and tries not to smile too hard at the way Shiro so effortlessly carries him through his apartment and towards his room.

Shiro nudges open his door with his foot, careful of Keith’s head as he passes through his bedroom doorway, and lays Keith on his bed more tenderly than a flower to ones grave. His gaze is this soft, careful thing, but there’s no mistaking all the raw hunger beyond the greys of his eyes. 

Keith reaches out, fingers massaging up and behind Shiro’s neck, before bringing Shiro down into his orbit. Lips meeting for a kiss that somehow feels more raw and more naked than all the others before it. Tongue moving over his lips to invite Shiro in, the bigger man relaxes and moves over him. Chasing his kisses, his body with his own.

Straddling the younger man beneath him, Shiro’s hands begin to move. Starting at the soft dip in his abdomen, and searching. One hand slips up his shirt and pets sweetly at the soft skin there. Keith’s strong, but unlike Shiro, his body seldom shows it. Keith is all lean muscle and soft skin, smooth horizons. But as Shiro feels further up, he finds his nipples hardened over the soft bumps of his chest. Smirking as he rubs over them once, twice, then squeezing the hardened bud between his fingers.

It’s enough to make Keith gasp into the middle of their kiss, which Shiro swallows with a laugh.

“Fuck.”

“Sensitive?” Shiro asks, a laugh on his breath. “You’re so cute.”

“Fuck you.” Keith pants back, uncaring if his response is all that witty or not.

Up above him, Shiro couldn’t be more pleased. “Oh, I will. But first,” Shiro stops, and then moves to squeeze both his nipples in each hand. This time, it rouses a soft, fluttery little gasp that makes Keith crane his head back and flush from head to toe. Moaning loudly as Shiro rubs and squeezes and pulls at his sensitive little nipples.

“God. Baby.” Shiro says, overcome with his own arousal as he bends down over Keith. Breath ever warm, mouth hot on his neck. “You’re so fucking hot.” Shiro husks into Keith’s ear, sending shivers all up and down his body before kissing his neck.

“Oh, _ah- fuck_ Shiro.” Keith gasps, wholly overwhelmed by all Shiro’s praises and tormenting little touches. Hands no longer grasping behind his head, but falling askew over his back, where Keith attempts to hold on for dear life as Shiro absolutely ravages him. Some Omega instinct inside him must be awake and listening inside of him, because without knowing why, Keith finds himself opening his legs for his Alpha. And almost immediately, Shiro presses a knee there.

“ _Oh_ , _oh fuck_ —Shiro, Shiro,” Keith pleads unthinkingly, hips bouncing up onto Shiro’s leg and grinding there softly.

Keiths little pleas are only met with another one of Shiro’s terribly hot chuckles, before the older man pushes said leg even further up into him, and Keith groans. Nails digging into Shiro’s back as he grinds lowly over Shiro’s offered thigh.

“That’s it. That’s my good omega.” He praises, and just the words alone have Keith feeling like he might explode. “There we go. Just like that.”

Between Shiro teasing his nips and suckling softly at his neck, Shiro moves and drags Keiths shirt up and off of him. Not bothering at all to hide the predatory smirk pointed at the reddened , pink buds at his chest. Keith follows his eyes with a huffy-- if not flustered—little pout of his own, only for his expression to be wiped away when Shiro takes his own Shirt off in kind-- And then Keith is the one staring.

Oh _fuck_. Keith knew Shiro was big, but he didn’t know he was _that_ big. His shirt’s really do hide everything. All the bulging muscle of Shiro’s defined chest is suddenly at full display, and the reality of just how different they are in size and power is enough to make’s Keith’s head spin, and his face to absolutely catch fire and smoke.

Keith brings the tip of his thumb to his teeth and bites down with a hiss of _“Holy fuck.”_ There’s no way- No way he can deal with this and stay sane.

And then Shiro’s chuckling again, this time at Keith’s obvious arousal— And the humiliation of being caught so utterly entranced by his Alpha’s body is enough to make Keith hide his face.

And then Shiro’s laughing again. The bed dips as he brings himself close to Keith once more. “It’s okay, sweetheart. You can look as much as you want.” He soothes, but the way Shiro says it makes it clear he’s clearly enjoying it. Keith wonders which one is bigger—Shiro’s ego, or his tits?

Keith peeks through his fingers, pouting. “Jerk.” Shiro muffles his laugh to kiss at his hands, before taking each one in his own and holding them apart from Keith’s face. By the time Keith notices the distraction and begins struggling to free his wrists from Shiro’s grasp, Shiro’s mouth is over his own again. Swallowing down his frustrations and replacing them with pleased little moans. Keith can feel Shiro smirk when every other kiss and suck successfully makes him forget to struggle, and it sends another fresh wave of slick gushing out from underneath him.

Evidently, Shiro can feel it, because on cue his thigh shifts again into Keith’s groin, making his cock twitch and his throat go dry as his hips jump involuntarily.

He doesn’t even realize one of his wrists has been freed until one of Shiro’s hands is cupping over his groin, feeling how damp the seat of his pajama’s are. “Fuck, Keith.” Shiro whispers into the kiss. “You’re so wet.”

Keith breaks the kiss off with an exasperated whine. “And who’s fault is that?” He asks with a half hearted little glare. Keith only acts like a petulant child with Shiro, and Shiro knows he only acts like that when he’s embarrassed. And in turn, Shiro has permission to handle him like one, the both of them knowing the act is all in mutual enjoyment for each others hidden sides. Keith with his softness, Shiro with his roughness and control.

So it’s with absolutely no attempt to hide his enjoyment for all of it, that Shiro moves down and says, “Don’t worry baby. Your Alpha will make it all better soon.”

Without warning, Shiro suddenly moves off of the bed from him only to hook his thumbs into his pants and underwear and them down with one fluid motion. Freeing his hefty cock and knot from their cotton prison so fast that Keith can’t help but stare at it. Not only is it his first time seeing so much of Shiro like this, but he can’t quite believe how big Shiro is either. Size had never been a factor to Keith in their relationship, but he can’t say that seeing Shiro so huge and heavy isn’t something he’s going to remember after he leaves.

Rejoining Keith on the bed, Keith can’t help but greet him with a wriggle and whine from his absence. Shiro hasn’t been gone for more than thirty seconds, but he's already needy with arousal.

Keith brings his legs up over his chest as Shiro dips his knee into the bed without prompting, and Shiro admonishes it with a little praise of “Good boy,” before wresting Keith’s own soaked pajama bottoms and briefs off of him.

“Alpha,” Keith says. The word gets Shiro’s attention like no other. Shiro turns onto Keith like a shark, and leans down over him. Body moving close over his own once more, Shiro’s large length hanging in between his legs and brushing over Keith’s cheeks.

Keith spreads himself once more for Shiro, who’s bare brushing against his slick hole is enough to make him feel as though the warmth in his gut might just consume him if Shiro doesn’t keep touching him.

Keith wriggles his hips impatiently, a sudden neediness taking him from Shiro’s absence. “Alpha-Alpha please—“

“Hold on sweetheart,” Shiro says, taking one of Keith’s thighs in one hand and lining himself up with another. “I’ve got you. Just a little more.”

As Shiro’s cockhead brushes, and then lightly presses against Keith’s wet, wanting entrance, Keith’s briefly reminded of all those stock-images of happily mated Alpha’s and Omega’s. Of hallmark greeting cards and lifetime movies, where Alpha’s are these big towering muscled men and women, and Omega’s are their weak, pliant little princes and princesses—And it takes him with another wave of terrible arousal when he realizes that that’s exactly what he is right now. A sweet, good, obedient little omega. Ready and wanting for his Alpha’s cock.

And fuck if maybe that doesn’t just make it hotter.

Another wave of slick seeps out of him with his thoughts, and Shiro looks up to his flushed face. As if wondering what exactly prompted it. Teasingly, his spreads Keith as wide as he can go and grinds the head of his big hard cock against Keith’s entrance.

“Is this want you want baby boy?” He asks, teasing. Keith bites his lips, his cheeks flaming hot with embarrassment. Toes curling. Cock leaking pre-cum over his soft belly from sheer arousal.

“You want your Alpha’s cock?”

Keith whines low in his throat, cheeks burning from the tease, and goes. “Yes Alpha. I want… “ He gulps. “Want your cock.”

Giving a pleased hum in his throat, Shiro takes Keith’s leaking cock in his hand and begins to pump it slowly, making Keith moan at the sight. “Do you want my knot too, sweetheart?” He asks. Shockingly sincere after the line of teases. Whether Keith gets impregnated or not from it is a non-issue—He’s been on a long form of contraceptives for over a year now. Shiro is aware of this, making it a non-issue. – No, what Shiro’s asking for right now, is purely about permission.

Shiro’s other hand finds his cheek then, and Keith places his hand over it, holding it there. Something about the vulnerability of it all has his voice hitching higher than it should when he finally gives his answer. The short little “Yes please.”, making Shiro smile, before he moves to give his omega a sweet, affectionate kiss.

“Alright sweetheart. You just let me know if you want me to stop, and I’ll stop. Okay?”

Keith nods, unable to help his own smile too. “Okay.”

With their understanding reached, Shiro takes a breath and lines them up again. The mushroom head of his cock brushing the ever-slick hole of his omega lover, before Shiro pushes it in.

Above him, Keith opens his mouth in a wordless gasp. Eyes clouding up even as he watches Shiro push into him. Keith hadn’t taken Shiro’s thickness into consideration, surprised at just how spread open he feels. Only once Shiro stops, does Keith breathe again. Little wanton “Ohh.. _Ohh,”_ s heaving out of him as he adjusts to Shiro’s size.

“Oh, Alpha-,”

“Yes, my omega?” Shiro asks dutifully. Sweat is starting to collect on his brows now, on his pecs and shoulders with the force of restraining himself. Keith is wet and warm and incredibly, dizzyingly pliant for him, and it’s taking much of his self control not to just jerk into him as it is. “Does it hurt?” He asks. His earlier teasing tone completely gone, as Shiro searches his lovers face for any sign of distress or discomfort.

“No, ahh. More. More Shiro. Please-“

“Fuck, Keith-“ Shiro bites out, cock jerking. Almost painfully hard hearing his omega whine for him, moaning so pretty when he’s not even half-way full.

“Please, Alpha?” Keith asks, and his voice is so soft and sweet. The plea coming out so utterly, completely sincere that Shiro can’t help but feel his heart tug just hearing it. Some Alpha instinct inside of him no doubt yearning to please his mate.

He doesn’t need to ask twice.

Immediately, Shiro Grips Keith by his hips and pushes deeper in. Despite trying to go as fast as he can for his Omega without hurting him, Shiro ends up slower than he’d like. Both out of concern for Keith, and because the heat of Keith’s hole is just that overwhelming. Somehow, it feels like it’s sucking him in, and Shiro finds himself pressing in all the way until Keith’s hole is pressed full to the brim with cock—All but his knot pressed deep inside of him.

The two of them take a second to catch their breath. Shiro gripping Keith’s hips painfully tight—Keith blissed out in fullness and pleasure. Babbling incoherently between little fucked-out moans, “So—so big.. Alpha. More- want more-“

“Fuck, baby.” Shiro spits out, restraint breaking in half as he finally, finally moves. Pulling out halfway, only to ram right back in, in one smooth motion. Hips snapping together and making Keith cry out in a long, beautiful moan that will no doubt play on repeat in Shiro’s mind every night for the next ten years.

“Yeah. There we go. You like that, baby?” Shiro asks, as he begins to thrust in and out of Keith. The man underneath him is so small and lithe, Shiro can manhandle him as he likes. He hips weigh practically nothing in his hands, and it’s all too easy to slide in and out at his leisure. And with every thrust comes another delicious little noise from his mate beneath him, driving Shiro hungrier and hungrier with each motion.

“Oh, god Shiro. Shiro,-- So big, so- Oh, fuck—“ Keith’s eyes are rolling back into his head, seeing stars and galaxies that don’t exist. One of his hands claw and clench at a pillow behind him, while his other mindlessly reaches out for Shiro.

“Alpha—“ Keith gasps, begging mindlessly. Fingers reaching blindly for him. Unable to catch his breath with Shiro filling him and fucking him so deeply. “Alpha, Alpha-“

Not needing any words at all, Shiro’s takes Keith’s hand in his own. Moving over him until they’re almost chest to chest, sensing his omega’s need to be close. “I’m right here baby. I’ve got you. I’ve got you.” He soothes between panted breaths. His other arm holding Keith down tight, even as his hips snap up in increasingly erratic thrusts. On instinct, Keith spreads his legs more and moves them up to straddle Shiro’s back. The change in position somehow making it all feel better than before, and Keith can’t help the soft little overwhelmed moan that ebbs out of him. “Ohhh.. Ohh god, yes.. Please. Alpha, it feels so good.”

Little does Keith realize that each and every one of his sounds are slowly driving Shiro to the brink of insanity. “Fuck, baby. You’re so hot.” He grunts, as if holding himself back. “If you keep saying that, I won’t be able to- to—“

And then to Shiro’s surprise, Keith’s hand is moving over his lips. When he looks down, he’s met with the deep violet of Keith’s soft, dreamy gaze. Cheeks and lips flushed red from love, eyes deep and consuming. Bearing more to Shiro than he’d ever thought possible. “It’s okay, Alpha. You don’t have to hold back.” He says.

Shiro’s eyes snap open, his whole body rigid for a moment. A choked breath in the back of his throat. Keith doesn’t know what he’s doing to him.

But of course, he continues. Ever oblivious, sweet and kind. His soft hand moving to cup his cheek with another little open mouthed moan. “Please, Alpha?”

With a short little gasp of “fuck,” under his breath, Shiro rams in to Keith. Forgoing all the carefulness and restraint he didn’t know he was still holding onto and ramming into Keith with reckless abandon, and making his omega yelp out in pleasure. His legs tightening around Shiro’s waist, desperately trying to keep more of Shiro in him as his thrusts become increasingly unstable.

Grunting, Shiro pounds into him again and again. Pressing himself into Keith as fast and as hard as he can. His head dipping into Keith’s shoulder, one arm squeezing him tight while his other hand squeezes his hip hard enough to leave bruises. “Fuck Keith. Fuck. You’re so cute baby. I love you, I love you so much. “ Shiro babbles. Nonsense praises and affections spilling from his lips to meet Keith’s own, drunken moans and whines.

“Alpha, Alpha Alpha Alpha-“ Keith cries, arms wrenching around Shiro’s neck and back to keep him as close as possible. “Alpha, I Love- Mine, my Alpha, my-- Shiro—I love- Love you t-Oh,Ohhhh-“ Without warning, Keith suddenly feels a large mass plunged into him, in addition to Shiro’s cock. Spreading him wider and fuller than ever before and pushing into him in one big powerful thrust that knocked all the breath from his lungs. Shiro’s knot had gotten so much bigger than when they first began, and now it was stuffed up inside of him-- filling him to the brim and setting off fireworks in the back of his brain. His toes curled and his hole clenched helplessly around the overwhelmingly large cocked stuffed into his ass, and Keith came in an open mouthed gasp.

In sequence, Keith could hear Shiro making a low, almost pained grunt from above him. His hips jerking erratically, before Keith felt a sudden warmth filling him from the inside. As if he wasn’t full enough. “Oh oh- ah, Alpha, Alpha-“ Keith whined, hips bucking up to match Shiro’s pace as he rode out his orgasm. All the while Shiro continued to fuck into him. Hands gripping him tight as Shiro spilled into him, too hot and too much and not enough all at once, in a mere three seconds.

As Keith’s breathing evens out and Shiro’s hips roll to a slow, lethargic cant, a new clarity blooms over Keith’s mind in a way he’s never felt before. It’s a calm, serene relaxation that’s already taking his headaches with it, and he can’t help but think about how Shiro was right. It really was a heat all along.

Exhausted, spent and sweaty, Shiro collapses in a heap next to Keith. Moving the now-very-attached omega with him and pressing him close in a tired, possessive cuddle that make’s Keith laugh in that cute little fucked out exhausted way. But this time, he doesn’t complain. Instead he adjusts his position so Shiro can cuddle him more easily while his Alpha takes his own time calming.

Once Shiro’s got his breath back, eyes closed and reveling in the soft afterglow of orgasm, Keith goes, “Well. I’m not getting any schoolwork done tonight.”

One amused grey eye cracks open at the remark. “No?” Shiro asks.

“Mm-mm.” Keith shakes his head. “Heats take a while to wear off, right?

“..Right.” Shiro nods, wondering where this is going.

“So.” Keith makes eyes at him. “What kind of a boyfriend would you be, if you didn’t show me what we were missing out on all night long?”

And really, how is Shiro supposed to argue with that?

/Fin


End file.
